syzbot

======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.6.886/9526 is trying to acquire lock:
ffff88805c9760a8 (&dquot->dq_lock){+.+.}-{3:3}, at: wait_on_dquot fs/quota/dquot.c:358 [inline]
ffff88805c9760a8 (&dquot->dq_lock){+.+.}-{3:3}, at: dqget+0x6fc/0xeb0 fs/quota/dquot.c:985

but task is already holding lock:
ffff88805c829818 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
ffff88805c829818 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}, at: ocfs2_reserve_suballoc_bits+0x16e/0x44c0 fs/ocfs2/suballoc.c:782

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}:
       down_write+0x97/0x200 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:804 [inline]
       ocfs2_remove_inode fs/ocfs2/inode.c:655 [inline]
       ocfs2_wipe_inode fs/ocfs2/inode.c:818 [inline]
       ocfs2_delete_inode fs/ocfs2/inode.c:1079 [inline]
       ocfs2_evict_inode+0x1d84/0x41e0 fs/ocfs2/inode.c:1219
       evict+0x4ca/0x8d0 fs/inode.c:705
       d_delete_notify include/linux/fsnotify.h:269 [inline]
       vfs_rmdir+0x39b/0x4d0 fs/namei.c:4217
       do_rmdir+0x29f/0x590 fs/namei.c:4263
       __do_sys_unlinkat fs/namei.c:4441 [inline]
       __se_sys_unlinkat fs/namei.c:4435 [inline]
       __x64_sys_unlinkat+0xc4/0xe0 fs/namei.c:4435
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #2 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]){+.+.}-{3:3}:
       down_write+0x97/0x200 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:804 [inline]
       ocfs2_del_inode_from_orphan+0x12f/0x7a0 fs/ocfs2/namei.c:2716
       ocfs2_dio_end_io_write fs/ocfs2/aops.c:2333 [inline]
       ocfs2_dio_end_io+0x546/0x1200 fs/ocfs2/aops.c:2431
       dio_complete+0x254/0x710 fs/direct-io.c:282
       __blockdev_direct_IO+0x2ea8/0x3500 fs/direct-io.c:1308
       ocfs2_direct_IO+0x235/0x2a0 fs/ocfs2/aops.c:2468
       generic_file_direct_write+0x1d4/0x3e0 mm/filemap.c:3956
       __generic_file_write_iter+0x11b/0x230 mm/filemap.c:4112
       ocfs2_file_write_iter+0x167a/0x1e80 fs/ocfs2/file.c:2468
       do_iter_readv_writev fs/read_write.c:-1 [inline]
       do_iter_write+0x738/0xc30 fs/read_write.c:860
       iter_file_splice_write+0x6a3/0xcb0 fs/splice.c:736
       do_splice_from fs/splice.c:933 [inline]
       direct_splice_actor+0xe8/0x130 fs/splice.c:1142
       splice_direct_to_actor+0x304/0x8c0 fs/splice.c:1088
       do_splice_direct+0x1d5/0x2f0 fs/splice.c:1194
       do_sendfile+0x5f2/0xef0 fs/read_write.c:1254
       __do_sys_sendfile64 fs/read_write.c:1322 [inline]
       __se_sys_sendfile64+0x145/0x1a0 fs/read_write.c:1308
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #1 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}:
       down_write+0x97/0x200 kernel/locking/rwsem.c:1573
       ocfs2_create_local_dquot+0x1a9/0x18f0 fs/ocfs2/quota_local.c:1224
       ocfs2_acquire_dquot+0x7f1/0xb10 fs/ocfs2/quota_global.c:871
       dqget+0x77c/0xeb0 fs/quota/dquot.c:990
       ocfs2_setattr+0xff1/0x1bc0 fs/ocfs2/file.c:1242
       notify_change+0xb0d/0xe10 fs/attr.c:499
       chown_common+0x413/0x5d0 fs/open.c:783
       vfs_fchown fs/open.c:851 [inline]
       ksys_fchown+0xed/0x160 fs/open.c:862
       __do_sys_fchown fs/open.c:870 [inline]
       __se_sys_fchown fs/open.c:868 [inline]
       __x64_sys_fchown+0x7a/0x90 fs/open.c:868
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&dquot->dq_lock){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain kernel/locking/lockdep.c:3869 [inline]
       __lock_acquire+0x2df1/0x7d40 kernel/locking/lockdep.c:5137
       lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x136/0xcc0 kernel/locking/mutex.c:747
       wait_on_dquot fs/quota/dquot.c:358 [inline]
       dqget+0x6fc/0xeb0 fs/quota/dquot.c:985
       __dquot_initialize+0x3c7/0xcd0 fs/quota/dquot.c:1518
       ocfs2_get_init_inode+0x148/0x1c0 fs/ocfs2/namei.c:202
       ocfs2_mknod+0x867/0x2300 fs/ocfs2/namei.c:310
       ocfs2_create+0x196/0x430 fs/ocfs2/namei.c:674
       lookup_open fs/namei.c:3496 [inline]
       open_last_lookups fs/namei.c:3564 [inline]
       path_openat+0x12a0/0x3230 fs/namei.c:3794
       do_filp_open+0x1f5/0x430 fs/namei.c:3824
       do_sys_openat2+0x134/0x1d0 fs/open.c:1421
       do_sys_open fs/open.c:1436 [inline]
       __do_sys_openat fs/open.c:1452 [inline]
       __se_sys_openat fs/open.c:1447 [inline]
       __x64_sys_openat+0x139/0x160 fs/open.c:1447
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

Chain exists of:
  &dquot->dq_lock --> &ocfs2_sysfile_lock_key[args->fi_sysfile_type] --> &ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3);
                               lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]);
                               lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3);
  lock(&dquot->dq_lock);

 *** DEADLOCK ***

3 locks held by syz.6.886/9526:
 #0: ffff88807a8a6418 (sb_writers#21){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
 #1: ffff88805c8f1818 (&type->i_mutex_dir_key#16){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
 #1: ffff88805c8f1818 (&type->i_mutex_dir_key#16){++++}-{3:3}, at: open_last_lookups fs/namei.c:3561 [inline]
 #1: ffff88805c8f1818 (&type->i_mutex_dir_key#16){++++}-{3:3}, at: path_openat+0x7dc/0x3230 fs/namei.c:3794
 #2: ffff88805c829818 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
 #2: ffff88805c829818 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#3){+.+.}-{3:3}, at: ocfs2_reserve_suballoc_bits+0x16e/0x44c0 fs/ocfs2/suballoc.c:782

stack backtrace:
CPU: 0 PID: 9526 Comm: syz.6.886 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
 check_noncircular+0x2fc/0x400 kernel/locking/lockdep.c:2187
 check_prev_add kernel/locking/lockdep.c:3134 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain kernel/locking/lockdep.c:3869 [inline]
 __lock_acquire+0x2df1/0x7d40 kernel/locking/lockdep.c:5137
 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
 __mutex_lock_common kernel/locking/mutex.c:603 [inline]
 __mutex_lock+0x136/0xcc0 kernel/locking/mutex.c:747
 wait_on_dquot fs/quota/dquot.c:358 [inline]
 dqget+0x6fc/0xeb0 fs/quota/dquot.c:985
 __dquot_initialize+0x3c7/0xcd0 fs/quota/dquot.c:1518
 ocfs2_get_init_inode+0x148/0x1c0 fs/ocfs2/namei.c:202
 ocfs2_mknod+0x867/0x2300 fs/ocfs2/namei.c:310
 ocfs2_create+0x196/0x430 fs/ocfs2/namei.c:674
 lookup_open fs/namei.c:3496 [inline]
 open_last_lookups fs/namei.c:3564 [inline]
 path_openat+0x12a0/0x3230 fs/namei.c:3794
 do_filp_open+0x1f5/0x430 fs/namei.c:3824
 do_sys_openat2+0x134/0x1d0 fs/open.c:1421
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x139/0x160 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f5aa3d9aeb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5aa4c04028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f5aa4016180 RCX: 00007f5aa3d9aeb9
RDX: 00000000000026e1 RSI: 0000200000000180 RDI: ffffffffffffff9c
RBP: 00007f5aa3e08c1f R08: 0000000000000000 R09: 0000000000000000
R10: 00000000fffffffb R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5aa4016218 R14: 00007f5aa4016180 R15: 00007ffed3e6ca08
 </TASK>